using Microsoft.UI.Input;
using Microsoft.UI.Xaml;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace UWPToWinAppSDKUpgradeHelpers
{
    [ComImport]
    [Guid("3A3DCD6C-3EAB-43DC-BCDE-45671CE800C8")]
    [InterfaceType(
        ComInterfaceType.InterfaceIsIUnknown)]
    interface IDataTransferManagerInterop
    {
        IntPtr GetForWindow([In] IntPtr appWindow,
            [In] ref Guid riid);
        void ShowShareUIForWindow(IntPtr appWindow);
    }

    public static class InteropHelpers
    {
        public static readonly Guid DataTransferManagerInteropIID =
            new Guid(0xa5caee9b, 0x8708, 0x49d1, 0x8d, 0x36, 0x67, 0xd2, 0x5a, 0x8d, 0xa0, 0x0c);

        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool GetCursorPos(out POINT point);

        [DllImport("kernel32.dll", CharSet = CharSet.Unicode)]
        public static extern IntPtr CreateEvent(
                IntPtr lpEventAttributes, bool bManualReset,
                bool bInitialState, string lpName);

        [DllImport("kernel32.dll")]
        public static extern bool SetEvent(IntPtr hEvent);

        [DllImport("ole32.dll")]
        public static extern uint CoWaitForMultipleObjects(
            uint dwFlags, uint dwMilliseconds, ulong nHandles,
            IntPtr[] pHandles, out uint dwIndex);

        [StructLayout(LayoutKind.Sequential)]
        public struct POINT
        {
            public int X;
            public int Y;

            public POINT(int x, int y)
                => (X, Y) = (x, y);
        }

        public static void ChangeCursor(this UIElement uiElement, InputCursor cursor)
        {
            Type type = typeof(UIElement);
            type.InvokeMember("ProtectedCursor", BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.SetProperty | BindingFlags.Instance, null, uiElement, new object[] { cursor });
        }
    }
}
